Note: Javascript is disabled or is not supported by your browser. For this reason, some items on this page will be unavailable. For more information about this message, please visit this page: About CDC.gov.

Basis for original (SCP) IDLH: No acute inhalation toxicity data are available on which to base an IDLH for hydroquinone. For this draft technical standard, therefore, the respirators have been selected on the basis of the assigned protection factor afforded by each device up to 100 ´ the OSHA PEL of 2 mg/m3 (i.e., 200 mg/m3); only the "most highly reliable" respirators are permitted for use in concentrations exceeding 200 mg/m3. This concentration is not likely to be attained in industry.

Short-term exposure guidelines: None developed

ACUTE TOXICITY DATA:

Lethal dose data:

Species

Reference

Route

LD50

(mg/kg)

LDLo

(mg/kg)

Adjusted LD

Derived value

Mammal

Mouse

Rabbit

Rat

G. pig

Dog

Cat

Kazpuchina 1979

Korolev et al. 1973

Takahashi 1975

Woodward et al. 1949

Woodward et al. 1949

Woodward et al. 1949

Woodward et al. 1949

oral

oral

oral

oral

oral

oral

oral

490

245

200

320

550

200

70

-----

-----

-----

-----

-----

-----

-----

3,430 mg/m3

1,715 mg/m3

1,400 mg/m3

2,240 mg/m3

3,850 mg/m3

1,400 mg/m3

490 mg/m3

343 mg/m3

172 mg/m3

140 mg/m3

224 mg/m3

385 mg/m3

140 mg/m3

49 mg/m3

Human data: It has been reported that 5 to 12 grams is the lethal oral dose [Zeidman and Deutel 1945]. [Note: An oral dose of 5 to 12 grams is equivalent to a worker being exposed to 3,333 to 8,000 mg/m3 for 30 minutes, assuming a breathing rate of 50 liters per minute and 100% absorption.]

Revised IDLH: 50 mg/m3

Basis for revised IDLH: No inhalation toxicity data are available on which to base an IDLH for hydroquinone. Therefore, the revised IDLH for hydroquinone is 50 mg/m3 based on acute oral toxicity data in humans [Zeidman and Deutel 1945] and animals [Woodward et al. 1949].